Running our Furnace

[Snowyowl]

The nights are starting to dip down to freezing. The tank heaters are turned on but, because I'm concerned about the water lines freezing, last night I turned on the furnace and set the thermostat to 40 degrees. This morning I went out to check and the temp. in the trailer was 36.7 degrees so apparently the furnace didn't kick in. I turned the thermostat to 50 degrees and the furnace came on so I'm assuming that there is a minimum temperature before the thermostat turns the furnce on. I will experiment to see what that min. temp. might be. Since all I want is enough heat to stop things freezing, there isn't any point in setting things higher than is absolutely necessary. Has anyone else done anything similar?

[Bama Rambler]

Your t-stat isn't very accurate at the lowest of highest setting so you may have to move it off the bottom a little to get it to operate correctly.

[MtnGuy]

An RV thermostat will not keep the temperature exact. It might have turned on during the night, and raised the temperature to 45, the maybe it won't cut back on until the temperature goes back to 35. Or, the thermostat is off a couple of degrees, resulting in the low temperature. On some RV thermostats, there is a cycle function so the furnace doesn't cycle too often. Mess with the thermostat a couple more of the cold nights, and see if it isn't working correctly.

I do what you do in early spring and late fall if the trailer isn't winterized during cold weather. I don't have tank heaters, so I rely on the ductwork near the tanks, and will also put some rope lights around the dump valves to keep that area from freezing.

[08flagvlite]

Those factory installed RV thermostats are not very good quality. You can install a new thermostat that is digital, and far more accurate pretty easily yourself, as many folks on this forum have done. There are several good posts about this, and show how to wire them in, as well. Also, be aware that the heaters in these campers are big propane hogs- keep a check on the tank levels! Randy

[MtnGuy]

I remembered something from a year or so back concerning after-market thermostats for an RV and had copy and pasted that for my future reference.

It reads: "We recently had a minor problem with the A/C, and had a mobile RV technician come out to our campsite to fix it. Great guy, knew his stuff really well, and very reasonable rates. Anyone need a mobile RV mechanic around Charlotte, NC area, PM me, I'll give you his number.

Anyway, I mentioned to him the idea I'd read about on here, about replacing the thermostat with the digital ones you can buy many places. He told me in no uncertain terms, that replacing the thermostat with one that was not designed specfically to work with your A/C unit (i.e, buying a Hunter digital thermostat to work with a Dometic or Coleman A/C), is asking for trouble, and a very BAD idea.

May well work OK for a while, but fact is you are changing the cycling frequency, etc. to something that the A/C unit was not designed to do. He told me he has replaced many, MANY entire A/C units, because people put on those digital thermostats, and eventually broke something with the main A/C unit. If you want the A/C to last and work within the design parameters it was intended for, his advice was to stick with using a thermostat that was made specifically to work with your actual A/C unit.

I know that this is a popular mod, so many will disagree and get defensive saying they've done this mod and never had a problem for years. And they'll probably question if this RV tech knew what he's talking about. I'll answer that last question now: I spoke with this guy for a long time, and can tell you he's beeng working on various RV systems for many, MANY years, and he knows what he is talking about. I don't doubt that these digital thermostats work and are an improvement, and its obvious from posts on here that some 'get away with this' without any problems for a long time. HOWEVER, I think I'm going to stick with the advice of the RV professional that works on RV A/C units for a living, and stick with the Dometic thermostat ours came with."

I think I got that off of RV.net.

Just a FYI.

[Bushman512003]

That is bunk all the way I have ran digital.stats for years and not one problem as hunders of others have also changed them out never read a post against it before .Just controles the on off of the heat and cold to a closer cycle in tolernence so You can save gas in heating and not freeze in cooling Your rig.But not saying You will not Be first to have a problem I am not a Heat & vent Guy but have a friend that is and He said the same thing Bunk....Bushman

[08flagvlite]

I have a friend that works for Carrier, he's been with them for at least 30 years, and he said it is not a problem, as it only controls the cycling on and off more accurately. In addition, most can be set with an adjustable 2 minute or 5 minute on delay designed for compressor safety. They use batteries instead of the 7.5 volt power source from the camper. Randy